The CHADS₂ versus the New CHA₂DS₂‐VASc Scoring Systems for Guiding Antithrombotic Treatment of Patients with Atrial Fibrillation: Review of the Literature and Recommendations for Use

Abstract

The association of atrial fibrillation and resultant thromboembolic stroke is readily recognized in the published literature. However, the identification and weight of other risk factors that increase stroke risk are varied. To predict which patients are at greatest risk for thromboembolic stroke, numerous risk stratification schemas have been developed to guide thromboprophylactic treatment decisions. The well-known CHADS(2) scoring system incorporates risk factors such as congestive heart failure, hypertension, age 75 years or older, diabetes mellitus, and previous stroke or transient ischemic attack. Recently, a novel risk stratification model, CHA2DS2 -VASc, has entered the literature and international guidelines, prompting further review of newly added risk factors-age 65-74 years, presence of vascular disease, and female sex-and the increased allotment of 2 points (vs 1 point in CHADS2) for age 75 years or older. The rationale for CHA2DS2 -VASc, as put forth by its authors, is that other risk assessment models omit important risk factors, have low predictive ability, and categorize too many patients as intermediate risk, leaving the choice of anticoagulant or antiplatelet therapy to the discretion of the clinician. Although CHA2DS2 -VASc readily identifies those patients truly at low risk, it classifies more patients as high risk who would then receive anticoagulation therapy. Therefore, implementation of this risk schema warrants further evaluation, especially when weighing the risk for bleeding and the risk for stroke. This critical review provides practitioners with an understanding of the literature that prompted the inclusion of these new risk factors and increased point allocations, compares and contrasts the risk schemas, and reviews national and international guidelines, thereby equipping the health care provider with the knowledge to aid clinical decision-making.

Suboptimal use of non-vitamin K antagonist oral anticoagulants

“…[21] The incidences of stroke increase with increase in CHA 2 DS 2 VASc scores; however, the recommended dose of NOAC is not associated with this risk category and only OAC without antiplatelet therapy is recommended for patients at risk of stroke. Similarly, in this study, the prevalence of OT was increased with the increase of CHA 2 DS 2 VASc score and antiplatelet agents were more often used in patients from OT group than UT and AT groups.…”

Inpatient Mortality Risk Scores and Postdischarge Events in Hospitalized Heart Failure Patients

“…16,17 An exception may be the use of simple stroke risk scores for atrial fibrillation patients which are more widely used 18 despite modest to moderate and highly variable discriminative power demonstrated in different validation studies. 19 Model complexity and skepticism regarding the accuracy of the models in providers’ unique practice settings are believed to limit use of risk scores. 4 To address these barriers to implementation, here we assessed simple models in a single center, community setting.…”

Atrial Fibrillation Genetics: Is There a Practical Clinical Value Now or in the Future?

“…Clinically, current AF related stroke risk is estimated using risk prediction scores such as CHADS2 and CHA 2 DS 2 VASc, 50 yet these prediction tools are obviously imperfect. Prior observations suggest a heritable component underlying ischemic stroke, with an estimated 37.9% heritability associated with all ischemic strokes and 32.6% for cardioembolic strokes.…”